overseas into the giant arena where 100 of the most powerful leaders on the globe were gathering in the pouring rain with thousands of people celebrating the singular life of nelson mandela. We have team coverage tonight. Abc's byron pitts and we begin with abc's chief foreign correspondent terry moran in pretoria. Reporter: Die Reporter: What a day, diane. A day of stirring songs and drenching rains, of soaring tributes and simple gratitude. Reporter: They made history in johannesburg today. Long live nelson mandela. Reporter: All those world leaders, 91 of them. The largest gathering ever for a memorial service like this. Paying tribute to one of their own. The great statesman, nelson mandela again. We will never see the likes of nelson mandela again. Reporter: But we really belonged to them. Ordinary south africans, his people. And they poured into fnb by the thousands, ignoring the cold soaking rain to say fair well to their leader to the man they call madiba. They seized the moment cheering and dancing and at times taking over the ceremony. Please tone down your singing. Reporter: Across the country south africa stopped to watch and listen. President obama who received a raucous welcome from the crowd spoke about mandela's closeness to his people. His struggle was your struggle. His triumph was your triumph. Reporter: Four u.S. Presidents attended this grand memorial service. That's never happened before overseas and they seemed to get into the festive spirit of the event. President obama joining the british and danish prime ministers in a selfie white president bush posed with bono of u 2. This may be the most controversial picture, president obama shaking hands with cuban president castro. Moments later a sharp jab at repressive rulers like castro. There are too many leaders that claim solidarity but do not tolerate it from their own people. Reporter: This was a family day, too. The entire mandela family here in mourning and celebration. On it went and no one seemed to want to leave to let go. We just have three more speakers -- Reporter: Archbishop desmond tutu, a friend of mandela tried to bring it to a close. I am not going to give you a blessing until all of you stand for the man. Reporter: They did mostly and then carried with them the brightness of the celebration, the gift he gave them, freedom. The body of nelson mandela is going to lie in state for three days just over there in the government buildings. But today their mourning turned into dancing as the bible says and that unforgettable feeling inside the stadium can only be described as an outpouring of love. That's quite a legacy for any man to leave. My colleague byron pitts was with those amazing crowds all day. Reporter: They came by foot by train, many arriving well before sunrise. This woman arrived six hours early. I can't feel the rain. It's an emotion I've never felt before, it's so nice. Reporter: The rain, nor my questions stopped her from dancing. We're so happy because he made south africa to be a rainbow nation as you can see black people and white people are sitting together. Reporter: Today, people were undaunted by the weather. The harder it rained, the harder they celebrated. Africans believe if it rains on the day of a person's funeral, it's a sign that person lived a blessed life. Amid the singing and celebrating people made clear to us, nelson mandela wasn't perfect, and major problems still exist. But when mandela became president in 1994, any became possible. We say long live the spirit of mandela. Reporter: One man told us, mandela spent 27 years in prison. A little rain won't stop us from celebrating his life. And diane, he added, celebrating it loudly.

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